The speed of light in a vacuum is approximately 299,792,458 meters per second. This value is a fundamental constant in physics, denoted by the symbol c. It represents the maximum speed at which all energy, matter, and information in the universe can travel. This incredible speed plays a crucial role in various scientific theories, including Einstein's theory of relativity. It helps explain how time and space are interconnected, influencing our understanding of the universe and the behavior of light, which is essential for technologies like GPS and fiber optics.